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''Kairuku grebneffi'' is an extinct species of giant penguin. It is among the tallest and heaviest penguins attested to, weighing 50% more than modern emperor penguins. The species is marked by a slender body and long, slender beak. ''K. grebneffi'' lived in what is now New Zealand during the late Oligocene, going extinct around 25 million years ago. The first bones of the species were discovered in 1977, but it was not classified as a distinct species until 2012. ==Description== ''Kairuku grebneffi'' were nearly long and stood tall. Adult individuals weighed an estimated , 50% more than modern emperor penguins.〔 ''K. grebneffi'' had the longest humerus bone of any penguin extant or attested to in the fossil record.〔 The bird had a longer beak and more slender body than those of modern penguins. Relative to its body size, its flippers were longer and probably more flexible than those of modern species.〔 It had short, thick legs, but overall looked a lot like a modern penguin "from a distance."〔〔 ''K. grebneffi'' is distinguished from its sister species ''K. waitaki'' primarily on the basis of vertebrae spacing and by having a straight tipped beak, compared to the curved tip of ''K. waitaki''.〔 Additionally, all known specimens of ''K. grebneffi'' are larger, although small sample size prevents that from being a diagnostic characteristic.〔 ''K. grebneffi'' likely used its slender beak to spear fish and squids.〔 It likely was able to dive deeper and swim farther than modern penguins.〔 Predators of the bird likely included sharks and ''Squalodons''.〔 ''K. grebneffi'' lived in what is now New Zealand late in the Oligocene period, roughly 25-27 million years ago. At the time, most the area was mostly ocean, with a few isolated islands.〔 It is believed that these rock outcrops provided safe breeding grounds and easy access to rich food resources in the surrounding seas.〔 ''K. grebneffi'' lived alongside at least four other penguin species. It is likely that each species fed on different kinds of fish. ''K. grebneffi'' was among of the last of the giant penguins.〔 The cause of ''K. grebneffis extinction is unknown, but was probably related to "the drastic change in paleoenvironment" according to Tatsuro Ando, one of the scientists who classified the penguin.〔 Other possibilities include the arrival of new predators and increased food competition.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Kairuku grebneffi」の詳細全文を読む スポンサード リンク
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